title: Accuracy of predictive equations for the measurement of resting energy expenditure in older subjects.
abstract: OBJECTIVE
  The measurement of resting energy expenditure (REE) is important to assess individual total energy requirements in older subjects. The validity of REE prediction equations in this population has not been thoroughly evaluated and therefore the main aim of this analysis was to assess the accuracy of REE prediction equations in older subjects.
  
  
  METHODS
  Weight, height and body mass index (BMI) were measured. REE was measured by indirect calorimetry (IC) in 68 older subjects (age: 60-94 years, M/F: 13/55, BMI: 26.3 ± 5.0 kg/m(2)). Measured REE was compared to 14 equations for the calculation of REE estimates. In addition, two novel approaches (Aggregate model and meta-regression equations) for the prediction of REE were evaluated. Paired t test and Bland-Altman method were used to assess the agreement of the equations.
  
  
  RESULTS
  The average measured REE was 1298 ± 264 kcal/day. The equation with the smallest bias was proposed by Muller (Bias ± 2SD = +3 ± 294 kcal/day) whereas the Mifflin equation was associated with the largest error (Bias ± 2SD = -172 ± 282 kcal/day). The Aggregate, Muller, Harris-Benedict and Fredrix equations were characterised by a prediction within ±10% of measured REE in more than 60% of subjects. Of the four algorithms, only the Aggregate equation did not show a significant association of the measurement bias with age, BMI and gender.
  
  
  CONCLUSIONS
  The Aggregate algorithm was characterised by a higher, overall accuracy for the prediction of REE in older subjects and its use should be advocated in older subjects. However, due to the large variability of the estimates, the measurement of REE by IC is still recommended for an accurate assessment of individual REE.
authors.affiliation: Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK. Electronic address: mario.siervo@ncl.ac.uk.
authors.forename: M
authors.initials: M
authors.lastname: Siervo
authors.affiliation: International Center for the Assessment of Nutritional Status, (ICANS), Department of Food, Environmental and Nutritional Science (DeFENS), Università degli Studi di Milano, Via Colombo 60, 20133 Milano, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Bertoli
authors.affiliation: International Center for the Assessment of Nutritional Status, (ICANS), Department of Food, Environmental and Nutritional Science (DeFENS), Università degli Studi di Milano, Via Colombo 60, 20133 Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Battezzati
authors.affiliation: Childhood Nutrition Research Centre, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK.
authors.forename: J C
authors.initials: JC
authors.lastname: Wells
authors.affiliation: Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, UK.
authors.forename: J
authors.initials: J
authors.lastname: Lara
authors.affiliation: Human Nutrition and Eating Disorders Research Centre, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Via Bassi 21, 27100 Pavia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Ferraris
authors.affiliation: Human Nutrition and Eating Disorders Research Centre, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Via Bassi 21, 27100 Pavia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Tagliabue
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001481:Basal Metabolism / Q000502:physiology*; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D002153:Calorimetry, Indirect; D003430:Cross-Sectional Studies; D002149:Energy Intake; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009751:Nutritional Requirements; D011237:Predictive Value of Tests; D015203:Reproducibility of Results
keywords: Ageing; Indirect calorimetry; Prediction equations; Resting energy expenditure